21583996 has 24 divisors (see below), whose sum is σ = 43879136. Its totient is φ = 9097920.

The previous prime is 21583993. The next prime is 21583997. The reversal of 21583996 is 69938512.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21583993) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4611 + ... + 8026.

Almost surely, 2^21583996 is an apocalyptic number.

It is an amenable number.

21583996 is an abundant number, since it is smaller than the sum of its proper divisors (22295140).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21583996 is a wasteful number, since it uses less digits than its factorization.

21583996 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12709 (or 12707 counting only the distinct ones).

The product of its digits is 116640, while the sum is 43.

The square root of 21583996 is about 4645.8579401441. The cubic root of 21583996 is about 278.4265315524.

The spelling of 21583996 in words is "twenty-one million, five hundred eighty-three thousand, nine hundred ninety-six".